Lamming has been part of the senior leadership team throughout Telstra's massive business transformation project. He advised on how to rationalise and integrate the company’s IT, operational and business support systems.

Lamming also had a stint as CIO from February 2007 until November 2008 before being replaced by John McInerney.

His role will be absorbed by the wider leadership team as Telstra's IT transformation moves to its next stage.

Trujillo said the IT transformation has touched every part of the company – from core operations to customer facing businesses - and Lamming had been there every step of the way.

“As a result of Tom’s world-class leadership and hard work, Telstra’s transformed IT systems are operating at scale and providing a single, integrated view of customers that will enable Telstra to deliver an unparalleled customer experience,” Trujillo said.

Trujillo said more than seven million customers have been migrated to Telstra's new platforms and more than 400 legacy systems and platforms have been decommissioned as part of the transformation.

“I thank Tom for his commitment to the cause and his lasting achievements at Telstra and wish him every success as he embarks on the next stage of his life.”

Lamming said his role at Telstra has been “one of the most challenging but rewarding” jobs that anyone could do.

“Telstra’s transformation is the largest, most comprehensive and successful I have ever seen, and we have implemented it at speed,” he said. “ The wider transformation has touched all parts of Telstra and the IT program has played a significant role.”

“All successful transformations are driven from the top. The team that is working on the IT transformation is world class and it has been a pleasure to work with them. I have every confidence that they will finish the job under the leadership of John McInerney.”

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